The present invention generally relates to the field of orthodontics, and more particularly to the design of dental positioning appliances precisely configured to interface with an orthodontic elastic member.
An objective of orthodontics is to move a patient's teeth to positions where function and/or aesthetics are optimized. Traditionally, appliances such as braces are applied to a patient's teeth by a treating practitioner and the set of braces exerts continual force on the teeth and gradually urges them toward their intended positions. Over time and with a series of clinical visits and adjustments to the braces, the practitioner adjusts the appliances to move the teeth toward their final destination.
More recently, alternatives to conventional orthodontic treatment with traditional affixed appliances (e.g., braces) have become available. For example, systems including a series of preformed appliances/aligners have become commercially available from Align Technology, Inc., Santa Clara, Calif., under the trade name Invisalign® System. The Invisalign® System is described in numerous patents and patent applications assigned to Align Technology, Inc. including, for example in U.S. Pat. Nos. 6,450,807, and 5,975,893, as well as on the company's website, which is accessible on the World Wide Web (see, e.g., the url “www.invisalign.com”). The Invisalign® System includes designing and/or fabricating multiple, and sometimes all, of the aligners to be worn by the patient before the aligners are administered to the patient and used to reposition the teeth (e.g., at the outset of treatment). Often, designing and planning a customized treatment for a patient makes use of computer-based 3-dimensional planning/design tools, such as Treat™ software from Align Technology, Inc. The design of the aligners can rely on computer modeling of a series of planned successive tooth arrangements, and the individual aligners are designed to be worn over the teeth and elastically reposition the teeth to each of the planned tooth arrangements.
While recently developed orthodontic treatment technologies, such as those described above, represent a considerable advancement in the field of orthodontics, additional advancements remain of interest. For example, in some instances it may be advantageous to use an orthodontic elastic member to generate a tension force between a patient's upper and lower teeth to bring the teeth and/or jaws into a desired occlusion. In some traditional approaches, brackets are bonded to teeth in the upper and lower jaws and an orthodontic elastic member is used to couple the brackets to generate the tension force. Generating such a tension force in conjunction with recently developed orthodontic approaches can be challenging. For example, shell aligners are often designed to match the geometry of a patient's teeth, thereby leaving little room for bonding such brackets to a patient's teeth. In some cases, dental practitioners are left with the daunting task of trimming or otherwise self-manipulating shell aligners to receive orthodontic elastic members such as elastic bands and/or adapt to existing orthodontic appliances such as brackets already disposed on the patient's teeth. As such, there is a need for shell aligners that can be used in conjunction with an orthodontic elastic member to, for example, bring a patient's teeth into a desired occlusion.